1. Field of the Invention
The present invention relates to communications terminals and, more specifically, to communications terminals which receive data for their internal start-up of applications, and perform data authentication as to the received data.
2. Description of the Background Art
In a conventional system structured by a server and terminals, data is forwarded from the server to the corresponding terminal for application execution therein. For a game application, for example, the server may forward data including information about any other users and game settings to the corresponding terminal for its game play. Such data is continuously updated on the server side to be ready for a data request coming from the terminal side prior to game play, and thus the game data does not fail to be the latest.
Such a system requires data authentication to see whether the data coming from the server has been tampered or not. The terminal thus accordingly goes through data authentication by digital signature, digital watermarking, or the like, to verify the identity of the data, or the possibility of data tampering, for example.
An exemplary system for verifying the authenticity of Web pages has been disclosed in Japanese Patent Laid-Open Publication No. 2000-227757. Data authentication in this Publication is performed with respect to contents derived by the server using a Web browser.
The issue here is, a program for data authentication is often incorporated in an application, or have some relevance to any specific application. That is, an application and a data authentication program have a one-to-one relationship, which is unalterably established. Thus, changing the authentication mode for any specific application means newly installing a program therefor.
As such, in the conventional system for data authentication, changing authentication modes on an application basis has been very troublesome. What is worse, if the program is of a type incorporated in the application, the application has to be troublingly installed also.